With
mainstream acceptance of HDTV, virtually all digital sets
arriving on the market today are widescreen 16:9 format. What does it mean to
the typical consumer? That would depend on your viewing
material.

Standard
Definition images on Widescreen TV

Transition
period from the older 4:3 to 16:9 TVs are virtually
complete on the store shelves, but same is untrue for
most of the channels that we receive which are still in
standard definition, posing a dilemma of what to do
about the differential in the screen aspect. As
shown below in the 480p digital TV broadcast, sidebars
can cause uneven wear resulting in burn-in on certain
types of displays, but stretching the image distorted
the aspect and affect picture quality. Another
step change in the aspect ratio, from 16:9 to 2.35:1
often found in cinematic film transfers can cause even
further letterboxing if the whole frame is viewed in
entirety.

Standard Definition 480p Digital TV

True HDTV image in 1080i on local CBS
broadcast

Most
displays have options that can be set by the user,
commonly described as normal
(with bars on both sides also known as pillarbox), stretched
(filled from side to side), or zoomed (stretched
in all directions and then cut off on top and bottom to
retain the proper aspect) modes.

Widescreen
HDTV broadcasts on 4:3 TV

Although
no longer a common sight, a 4:3 aspect ratio HD-Ready/HDTV will display
widescreen HDTV broadcasts by letterboxing the image and placing
bars on the top and bottom, or by zooming into the image and
cutting off the sides.